rizky_p

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I have M@g P7 running @ 2.8A. should i add 1 or 2 more 7135? is it worth it? will it get much brighter?

Thanks
 
You get more unit heat per unit light as you add current.

You could add lots more current and it would look brighter, but the emitter would not last. And it would run very, very hot.
 
I would really be interested in how far you can push a P7 before it dies.
Seing that the Cree q5s could be pushed to 2A, and is bonding wire limited, with really good heatsinking the P7 should be easily able to get much higher..
 
My DD P7 mag will run at 6 amps for the first 30-40 minutes on AccuPower LSD D cells. It's bright as hell and gets pretty hot, but it levels off at around 3-4 amps the rest of the run before rapidly dropping off.
 
My DD P7 mag will run at 6 amps for the first 30-40 minutes on AccuPower LSD D cells. It's bright as hell and gets pretty hot, but it levels off at around 3-4 amps the rest of the run before rapidly dropping off.

6Amps??? that is 1.5A to each LED. :devil: I dont even have guts to run each @1A. Cree XR-E are rated @700ma but it is considered normal to run them @1A and some push it to 1.5A so how about P7 considering the same analogy.
 
After it was damaged, and i didnt care anymore, i ran my P7 at 4A.

Quite a bit brighter than at 2.8A, so it seems there is little "droop" going on.
 
The P7 is a SSC (Seoul) led, not a Cree-XRE led.

Although these 2 different products share the same die, they are different
in other respects such as the surrounding material, phosphor etc.

In general, from what I have gathered, SSC P4 leds are less robust than
Cree-XRE leds and one would certainly not want to push a SSC P4 beyond
1A at the very maximum.

Therefore I would assume that this applies to the SSC P7 led too.
 
My DD P7 mag will run at 6 amps for the first 30-40 minutes on AccuPower LSD D cells. It's bright as hell and gets pretty hot, but it levels off at around 3-4 amps the rest of the run before rapidly dropping off.

How many D cells is that?
 
...and one would certainly not want to push a SSC P4 beyond
1A at the very maximum.

Therefore I would assume that this applies to the SSC P7 led too.

I too have read that about P4s here & I have to disagree after seeing my own results. Only if there is insufficient heatsinking then over 1A is bad. I have a U2SWOI on a PM6 McModule running a DB1200. It's currently the brightest P4 I have in my collection & I don't have any problems with it getting angry blue. I've ran it for 15 mins continuously. I also have a USXOH on a Hotlips running DD in a Mag3C. On a fresh charge it is well over 1A and it doesn't get angry blue even after 2 mins but that's when current drops below 1A.

I've driven a CSWOI at 4A for 5 mins. Never got angry blue. I stopped it cause the heatsink I had it on got way too hot. It was a bit brighter to my eye than at 3A but it generated way too much heat very fast. Not sure if it is worth it. I'll try again another day.
 
The P7 is a SSC (Seoul) led, not a Cree-XRE led.
Although these 2 different products share the same die, they are different
in other respects such as the surrounding material, phosphor etc.
In general, from what I have gathered, SSC P4 leds are less robust than
Cree-XRE leds and one would certainly not want to push a SSC P4 beyond
1A at the very maximum.
Therefore I would assume that this applies to the SSC P7 led too.
I too have read that about P4s here & I have to disagree after seeing my own results. Only if there is insufficient heatsinking then over 1A is bad. I have a U2SWOI on a PM6 McModule running a DB1200. It's currently the brightest P4 I have in my collection & I don't have any problems with it getting angry blue. I've ran it for 15 mins continuously. I also have a USXOH on a Hotlips running DD in a Mag3C. On a fresh charge it is well over 1A and it doesn't get angry blue even after 2 mins but that's when current drops below 1A.

I've driven a CSWOI at 4A for 5 mins. Never got angry blue. I stopped it cause the heatsink I had it on got way too hot. It was a bit brighter to my eye than at 3A but it generated way too much heat very fast. Not sure if it is worth it. I'll try again another day.
The P7 is constructed differently than the P4,and I believe even the current P4's have this new process in place,thats why the new P4's dont shift to blue over 1A.I'm in the process of trying to find the post about all of this.
Here is a post from Gryloc on what I've found so far:
Each die has a pair of bond wires each going to the anode and cathode, so they are electrically identical to a newer 4-bond wire Cree XR-E. Thermal conductivity is better per die since the dies are bonded directly to a copper slug (zinc plated?) versus the Cree XR-E, where the die is bonded to a copper pad, then a thin aluminum substrate.
-Tony
I'll keep digging for the other posts
Michael
 
I'll take a pic later of the reading. I know it's working correctly, all the other amp readings from my other lights check out.
 
I thought that I would post a link to a nearly forgotten thread on the P7 arfter it was released and a few samples got out (I had one).
http://www.candlepowerforums.com/vb/showthread.php?t=190954&page=2
Scroll down to my post (#45). It showed my latest readings of my sample P7.

Oh, and I do not remember if post #31 from this link was any newer or more helpful:
http://www.candlepowerforums.com/vb/showthread.php?t=190675&page=2

I have been meaning to do the same to the P7 that I got from KD lately, but I never got the chance. It has a lower Vf bin, so that seems promising. The newer P7 I have is already epoxied to a D-sized Maglite heatsink, so getting real measurements from the P7 in a flashlight would be cool. My previous tests were with the P7 attached to a huge aluminum heatsink (with thermal paste between). I will see how time allows since I will be busy or away from home in the next three weeks.

6A to a P7 is amazing. I would be hesitant to run the light for more than 5 minutes, but I can see myself push the P7 with that much current for short durations under close monitoring. I am currently limited to 5280mA max from my CC/CV adjustable power supply. I am confident that the dies and the bond wires can handle the current, but I now worry about junction temperatures (thanks evan9162) at those currents. I finally got a cheap thermocouple system from DX, but it act so strange, that I do not trust it to confirm if water is boiling at 100C (the meter is way off). Once I can find a better meter for a reasonable price, I can always try to find how I can solder the thermocouple to the slug, then filing it flat to secure to a heatsink.

-Tony
 
I think I would be checking my multimeter. Just doesn't sound right. :shrug:
Norm

No, sounds right.
Fresh NiMh are >1.2V. And the low discharge ones dont have a lot of voltage drop.
A -I bin P7 will draw 3A at 3.6V, and >4A at 3.9.

If his cells are at 1.3-1.4V during the first minutes of discharge, thats certainly possible.
 
I concerned about this, as I just bought some of those Accupower LSD D cells to run my P7. How can this be any different than a Li-Ion cell that charges over 3.7V as well?

Do you think it's something unique about your P7? Has anyone else tested this many amps using 3 D cells?
Does a P7 B bin pull less amps than a C bin?
 
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I wouldn't be too concerned about it. If you use a stock light then you won't get anywhere near as much current. I replaced the switch with one of the low resistance10 amp click switches [forget the name] and use 14gauge wire for the led. I also use a 6 gauge solid copper ground wire for my tailcap spring. Add all that together and the resistance of my mag is practically nil.
 
I concerned about this, as I just bought some of those Accupower LSD D cells to run my P7. How can this be any different than a Li-Ion cell that charges over 3.7V as well?

Do you think it's something unique about your P7? Has anyone else tested this many amps using 3 D cells?
Does a P7 B bin pull less amps than a C bin?

Well, its not different, I _damaged_ my P7 by running it in direct drive from a fresh 18650 cell at 4.2V. I am not going to retry it, but it seems i hit at least 5Amps during that burst, maybe quite a bit more.

The voltage drop of those cells is not that big. Non-fresh, a single cell in direct drive is about 3.55V, which is about 2.5A. Thats not a big drop from 3.6-3.7.

Not think what will hapen if a fresh cell only drops to 4.0V...
 
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